UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 10-Q [ X ] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 or [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the period MAY 28 TO JUNE 30, 1999 Commission File Number: 000-26091 TC PIPELINES, LP (Exact name of registrant as specified in its charter) Delaware 52-2135448 ------------------------------- --------------------- (State or other jurisdiction of (I.R.S. Employer incorporation or organization) Identification Number) Four Greenspoint Plaza 16945 Northchase Drive Houston, Texas 77060 - ---------------------------------------- --------------------- (Address of principal executive offices) (Zip code) (281) 873-7774 -------------------------------------------------- Registrant's telephone number, including area code Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such report(s), and (2) has been subject to such filing requirements for the past 90 days. Yes [X] No [ ] THE REGISTRANT HAD 14,690,694 COMMON UNITS OUTSTANDING AS OF AUGUST 31, 1999.

PART II. OTHER INFORMATION TC PIPELINES, LP ITEM 6. Exhibits and Reports on Form 8-K (a) Exhibits. Exhibit 27. (b) Reports on Form 8-K. None.

SIGNATURES Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. TC PIPELINES, LP (a Delaware Limited Partnership) By: TC PipeLines GP, Inc., its general partner By: /s/ ------------------------------------- Date: August 31, 1999 Theresa Jang Controller

  

5 THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE SHEET AND INCOME STATEMENT FOUND ON PAGE 3 OF THIS PARTNERSHIP'S FORM 10-Q FOR THE YEAR-TO-DATE, AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS. 1,000 6-MOS DEC-31-1999 JAN-01-1999 JUN-30-1999 300 0 0 0 0 300 0 0 245,081 444 0 0 0 0 244,637 245,081 0 0 0 0 0 0 0 0 0 2,986 0 0 0 2,986 0.17 0.17